Not applicable.
Not applicable.
The present invention relates to a valve for dispensing a product from a container. The valve is especially suitable for use in a dispensing closure for a flexible container which is squeezable.
There are a wide variety of packages which include (1) a container, (2) a dispensing system extending as a unitary part of, or attachment to, the container, and (3) a product contained within the container. One type of such a package employs a dispensing valve for discharging a single stream of product (which may be a liquid, cream, or particulate product). See, for example, the package shown with the valve identified by reference number 3d n FIGS. 26-29 of U.S. Pat. No. 5,377,877.
The disclosures of U.S. Pat. No. 5,377,877 are incorporated herein by reference hereto. The package disclosed in the patent includes a flexible, resilient, self-sealing, slit-type valve at one end of a generally flexible bottle or container. The preferred embodiment of the valve is normally closed and can withstand the weight of the product when the container is completely inverted, so that the product will not leak out unless the container is squeezed. When the container is squeezed and the interior is subjected to a sufficient increased pressure, and/or when the exterior of the valve is subjected to suction, the valve opens. In the preferred embodiments described in U.S. Pat. No. 5,377,877, the valve stays open until the pressure differential across the valve drops below a predetermined value, then the valve then snaps closed. The valve can also open inwardly to vent air into the container when the pressure within the container is less than the ambient external pressure, and this accommodates the return of the resilient container wall from an inwardly squeezed condition to the normal, unstressed condition.
The accompanying drawings that form part of this specification include FIGS. 1-4 which are simplified illustrations of the above-identified conventional valve. In FIGS. 1-4 that form part of this specification, the valve is indicated generally by the reference number 303. As shown in FIGS. 1 and 2, the valve 303 includes a marginal portion or flange 304, and a valve head or head portion 305 connected to the flange 304 with a flexible connector sleeve 307. The valve 303 has a single orifice 306 (FIGS. 3 and 4) which is normally closed and which is defined by four slits 350 which radiate laterally from an origin defined by a longitudinal axis 349 through the valve 303 as shown in FIGS. 1 and 2.
As shown in FIG. 2, the valve has an exterior side or surface 338 and an interior side or surface 339. The valve 303 is installed on a container (not shown) so that the exterior side 338 faces outwardly and is exposed to the external ambient atmosphere. The interior side 339 faces the interior of the container and is exposed to the product and internal atmosphere within the container.
When a pressure differential is applied across the valve 303 as shown in FIGS. 3 and 4, the valve head portion 305 moves from an inwardly located position (FIGS. 1 and 2) to an outwardly located position (FIGS. 3 and 4), and the slits 350 open. Flaps or petals 357 are defined by the slits 350, and the flaps or petals 357 open as shown in FIGS. 3 and 4 to permit the contents of the container to be discharged. Typically, the valve 303 can be opened in response to a pressure differential applied across the valve by sucking on the exterior of the valve and/or squeezing a flexible container to which the valve is mounted.
In one conventional form of the valve 303, the valve closes after the pressure differential across the valve is reduced to, or below, a predetermined value which is lower than the minimum pressure differential necessary for initially opening the valve 303.
The conventional valve 303 has a reduced thickness region at its centerxe2x80x94at and adjacent the valve longitudinal axis 349. The laterally outer peripheral portion of the valve head portion 305 is thicker than the center. Such a structure has been found to provide desirable operating characteristics, including various opening characteristics and closing characteristics as more fully described in the above-identified U.S. Pat. No. 5,377,877.
While the above-discussed conventional valve 303 functions extremely well in many applications for which it is designed, there are some applications and potential uses for a dispensing valve wherein it would be desirable to provide different discharge flow characteristics. The inventor of the present invention has discovered that it would be beneficial in some applications to be able to provide multiple streams of product from a dispensing end of a closure on a container.
The inventor of the present invention has considered modifying the conventional valve 303 so as to include two or more orifices which could dispense two or more product streams simultaneously from a single valve. FIGS. 5-10 illustrate a prototype specimen of such a modified valve having three orifices, and the modified valve is designated generally by the reference number 403 in FIGS. 5-10.
The modified valve 403 has substantially the same shape and cross-sectional configuration as the conventional valve 303 discussed above with reference to FIGS. 1-4. The only difference is that the modified valve 403 has three orifices 406, each defined by four slits 450 in the valve head portion 405. Each orifice 406 defined by the slits 450 is laterally offset from the center of the valve (i.e., laterally offset from a longitudinal axis 449 passing through the center of the valve as shown in FIGS. 5 and 6). With reference to FIG. 6, it can be seen that the three orifices 406 defined by the slits 450 are necessarily located in the thicker part of the valve head portion 405. Further, some of the slits 450 or some portions of the slits 450 extend into thinner areas of the valve head portion 405, while other slits 450 or portions of the slits 450 extend into thicker areas of the valve head portion 405.
When a sufficient pressure differential is applied across the valve head portion 405 as shown in FIGS. 7 and 8, the valve head 405 moves from the inwardly recessed position to the outwardly extended position. As the pressure differential is increased, the valve orifices 406 begin to open (FIGS. 9 and 10). As shown in FIGS. 9 and 10, each orifice 406 defined by the slits 450 is surrounded by four flaps or petals 457A, 457B, 457C, and 457D. Flap 457A is closest to the center of the valve, flap 457C is furthest from the center of the valve, and flaps 457B and 457D are at intermediate positions relative to the center of the valve compared to flaps 457A and 457C.
As can be seen in FIG. 10, flap 457A can open further or wider than flap 457C because flap 457A has a thinner section 460 about which it bends compared to the thicker bending section 462 of the flap 457C. The orifice flaps may be characterized as being unbalanced and opening unequally. The flaps which are closer to the center of the valve are generally thinner and weaker, and they open further than do the flaps which are in the thicker, outer region of the valve head portion. Also, the thin central region of the valve head portion 405 tends to temporarily deform into an outwardly convex configuration so that the orifices 406 are positioned in an angled orientation relative to the valve longitudinal axis 449 such that the open flow path for the discharging product tends to be oriented at a diverging angle relative to the longitudinal axis 449. These conditions can cause the discharging product stream to be oriented at significant diverging angle relative to the longitudinal axis 449 of the valve. The product stream is schematically represented by the arrow 468 in FIG. 10.
Further, because each valve orifice 406, or part thereof, is located generally in the radially outer, thicker areas of the valve head 405, compared to a single orifice located in the central, thinner region of the valve head as in the conventional valve 303 illustrated in FIGS. 1-4, a greater differential pressure across the modified valve 403 is required to open the orifices 406 in the modified valve 403. This requires a greater effort on the part of the user who must suck harder on the outside of the valve and/or squeeze the container with greater force. This can contribute to a reduction in the flow rate of product being dispensed. This, of course, is generally not desired where a purpose of employing multiple orifices might be to increase the product flow rate.
The inventor of the present invention has discovered that it would be advantageous to provide a valve for dispensing multiple discharge streams of product which would be oriented with little or no divergence from the longitudinal axis of the valve. It would be desirable to provide a multiple orifice valve which could discharge multiple product streams in a relatively confined target area and which would not create significant diverging spray or splatter.
Such an improved valve should also facilitate ease of dispensing the product when the interior of the container is pressurized (e.g., when the container is squeezed or when the container internal pressure is increased by other means), or when suction is applied to the exterior of the valve. It would thus be beneficial if an improved valve could be provided with multiple orifices and that would not require an unduly large pressure differential to be applied across the valve in order to effect opening of the multiple orifices.
It would also be advantageous if such an improved valve could accommodate its use with bottles, containers, pouches, or packages that have a variety of shapes and that are constructed from a variety of materials.
Further, it would be desirable if such an improved valve could accommodate efficient, high-quality, large-volume manufacturing techniques with a reduced product reject rate to produce valves with consistent operating characteristics.
The present invention provides an improved dispensing valve which can accommodate designs having the above-discussed benefits and features.
The present invention provides a valve for dispensing a product from a container, and the valve has a unique configuration that opens when the pressure differential across the valve exceeds a predetermined amount (e.g., when the container interior pressure increases to a predetermined amount relative to standard atmospheric pressure outside the container). The valve can accommodate discharge of liquids, creams, or particulate matter, including powders.
The valve is adapted for use in dispensing a product from a container having an opening. The valve may be formed as a unitary part of an end of such a container or may be mounted in a separate assembly that is permanently or releasably attached to the container.
The preferred form of the valve is adapted for being sealingly disposed with respect to, and dispensing the product from, the discharge opening of the container. The valve includes a marginal portion adapted to be sealingly engaged when the valve is sealingly disposed with respect to the container discharge opening. The valve also includes a head portion that (1) is laterally inwardly of the marginal portion, (2) has an exterior side for interfacing with ambient environment, and (3) has an interior side for interfacing with the product.
In one embodiment, the valve head portion can be characterized as having a center or center region which is at least as thick as the periphery of the head portion. The head portion includes at least one normally closed orifice that is (1) offset laterally from the center of the head portion, and (2) defined by at least one slit that extends transversely through the head portion from the exterior side to the interior side whereby (a) flaps are defined by the slit, and (b) the orifice opens by outward displacement of the flaps in response to a predetermined pressure differential across the valve.
In a presently more preferred embodiment, the valve head portion exterior side has a generally concave shape when viewed from outside the container, and the head portion interior side has a generally curved, radially outer portion which tapers toward the periphery of the valve head portion such that the periphery of the valve head portion is thinner than the center of the valve head portion.
In a presently preferred form of the valve, the valve head portion includes two or more orifices where each orifice is defined by four slits diverging radially from an origin at 90 degree angles to define two mutually perpendicular, intersecting, longer slits. Preferably, the orifices are disposed uniformly in a circular locus on the valve head portion in the thinner regions of the valve head portion.
In a preferred embodiment, the valve also has a resilient, flexible, connector sleeve having (1) a first end portion thereof connected with the marginal portion of the valve, and (2) a second end portion thereof connected with the head portion. The connector sleeve has an interior surface for interfacing with the product and has an exterior surface for interfacing with ambient environment. The first end portion of the connector sleeve has a J-shaped cross section which extends into the marginal portion to facilitate movement of the head portion when dispensing product from the container. The connector sleeve preferably has a resiliently flexible sidewall with a configuration which extends rollingly to shift the valve head portion outwardly when the pressure differential across the valve increases above a predetermined amount.
Numerous other advantages and features of the present invention will become readily apparent from the following detailed description of the invention, from the claims, and from the accompanying drawings.